The present invention relates to hydrophilic cotelomers, having a terminal sulfonate group and containing acid and amine functions, as well as methods of preparing the cotelomers and compositions containing them.
Oligomers of acrylic acid and of acrylamide, having a terminal sulfonate group, are disclosed in U.S. Pat. No. 3,646,099. British Pat. No. 1,518,561 describes a process for modifying polymers of .alpha.,.beta.-unsaturated amides by halo-amidation of said polymers by means of a hypohalite in aqueous alkaline medium, followed by Hofmann rearrangement of the resulting halo-amide. This process is applied to products having average molecular weights higher than 5,000 and not containing any terminal sulfonate group. If the rearrangement reaction is partial and carried out at an excessively high temperature, the polymers obtained may simultaneously contain carboxylic acid, amide and amine groups.